Cellular telephone manufacturers are forever striving to decrease the size of their phones while, at the same time, striving to increase the number and complexity of the device's features. One example of such a feature is a digital camera integrated into the phone, which has become standard in newer phones. Not only has this feature become standard, with each new generation of phone, customers expect the resolution, speed, clarity, and other aspects of the camera to increase. Similarly, with each new generation, the phone's display screen increases in size and/or resolution. This increase in display capability works against the camera's performance, as it is becoming easier for a user to observe defects in the image captured by the camera.
With digital cameras, just as with conventional mechanical/film cameras, the amount of light that reaches the sensor is controlled with a shutter. The shutter opens to allow light passing through the aperture to reach the image sensor. The amount of time that the shutter is open controls the amount of light that the image sensor receives. Unlike film, the light sensor in a digital camera can be reset electronically, so, digital cameras have a digital shutter rather than a mechanical shutter. Therefore, when a camera captures an image, this image represents the scene over a period of time (exposure time).
If the camera, moves during the exposure time, the sensor will receive what is referred to as a “blurred” image—an image without well-defined edges and devoid of detail. Blurring is a natural result of a shaky hand, taking a picture while in a moving vehicle, taking a picture while walking, or many other causes.
To improve the image quality and compensate for camera shaking, conventional camera design requires mechanical movement of a lens or mirror to adjust an optical path length (OPL). Because prior-art lenses, mirrors, and the apparatuses to move them are too large for a cellular phone, prior art methods of reducing blur not practical.
Therefore, a need exists to overcome the problems associated with the prior art as discussed above.